For some, it helped explain why they had yet to find the perfect boyfriend. For others, the sudden shrinking of Britain's gay population last Thursday provoked sheer disbelief.

The report by the Office of National Statistics placed Britain's gay and bisexual community at 1.5% of the adult population, almost 750,000. Six years before, however, ministers had estimated the figure at almost 3.5 million.

The National Survey of Sexual Attitudes and Lifestyles, most recently conducted 10 years ago, asked 11,000 Britons: "Ever had sex with a same sex partner, including genital contact?" More than 6% of the respondents replied: "Yes." Are we to believe the pool of potential partners for gay and bisexuals has recently evaporated by millions? If not, then why the vast discrepancy?

The answer might be merely the latest example of a condition that has long blighted Britain's gay community: stigma. Last week's figures could represent how uncomfortable a large portion of the gay and bisexual population still feels when talking about their sexuality rather than suggest that previous calculations were awry.

The ONS survey asked a sample of 263,000 people to define their sexuality. Strangers appeared on doorsteps showing people a card of options and asking them to indicate which category they fitted into. It is an approach unlikely to persuade the large numbers of gay and bisexuals yet to emerge from the closet to do so, or to win confidences from those who don't like sharing personal information with people they don't know.

Government researchers, for instance, found many more refusals to answer questions on sexuality in the younger age brackets. An interesting trend can be found in relation to gay dating website Gaydar which has 1.5million UK profiles, most of them men. The key point is that the website is private. Obviously not all gay men are members and so, perhaps, the site's membership points to a more accurate picture than the ONS could ever hope to find.

Does the size of Britain's gay population really matter? Politically it might. When ministers introduced the civil partnership laws in 2004, a Treasury assessment indicated that up to 7% of the population was homosexual, a figure that may have been used to underscore the fact the government was acting on behalf of a significant minority. Most would agree that rights and protections should be extended to all individuals regardless of sexuality, class, race or religion.

Yet within hours of the ONS publishing its findings last week, calls had emerged from religious groups for less political attention and public money to be spent on meeting the demands of gay people. Right-wing newspapers talked of the figures "exploding the myth" that as many as one person in 10 was gay.

Whatever its size, the ONS survey did show that gay people may have the last laugh on those who cling to homophobic attitudes. Gay people, the survey found, are far more likely to be successful professionally and to be better educated.

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